Texas Instruments TravelMate LT286/12 keyboard
The photos below are archived from eBay listing 203160388678 “Vintage Compact NMB/HI-TEK Clicky Mechanical Keyboard Texas Instruments Laptop” from seller jonnyadler; the original listing has since been deleted by eBay. This is the keyboard from the Texas Instruments TravelMate LT286/12 portable computer, with Texas Instruments part number 2551587-0002. This keyboard uses an unknown type of NMB/Hi-Tek switch. The manufacture date was week 46 1989, and the serial number is 29002524. The manufacturer name is written “NMB/HI-TEK”; their model number was WSR-540A3 and their part number was 3057-7035. Potentially, WSR was the name of the series.
A nearly-identical keyboard appears on the TravelMate LT220, but that keyboard has different front-printed legends.
The Vintage Laptop Museum in Russia has reported that the LT286/12 keyboard is a mechanical type with click feedback.